Sub-packet pulse-based communications

ABSTRACT

Low power wireless communication techniques may be employed in devices that communicate via a wireless body area network, a wireless personal area network, or some other type of wireless communication link. In some implementations the devices may communicate via one or more impulse-based ultra-wideband channels. Inter-pulse duty cycling may be employed to reduce the power consumption of a device. Power may be provided for the transmissions and receptions of pulses by charging and discharging a capacitive element according to the inter-pulse duty cycling. Sub-packet data may be transmitted and received via a common frequency band. A cell phone may multicast to two or more peripherals via wireless communication links.

CLAIM OF PRIORITY UNDER 35 U.S.C. §119

This application claims the benefit of and priority to commonly ownedU.S. Provisional Patent Application No. 60/795,435, filed Apr. 26, 2006,and assigned Attorney Docket No. 061202P1, and U.S. Provisional PatentApplication No. 60/795,771, filed Apr. 28, 2006, and assigned AttorneyDocket No. 061202P2, the disclosure of each of which is herebyincorporated by reference herein.

CROSS-REFERENCE TO RELATED APPLICATION

This application is related to concurrently filed and commonly ownedU.S. Patent Application entitled “INTER-PULSE DUTY CYCLING,” andassigned Attorney Docket No. 061202U1; U.S. Patent Application entitled“DUTY CYCLING POWER SCHEME,” and assigned Attorney Docket No. 061202U2;and U.S. Patent Application entitled “WIRELESS DEVICE COMMUNICATION WITHMULTIPLE PERIPHERALS,” and assigned Attorney Docket No. 061202U4, thedisclosure of each of which is hereby incorporated by reference herein.

BACKGROUND

1. Field

This application relates generally to wireless communication and, invarious aspects, to inter-pulse duty cycling, a duty cycling powerscheme, sub-packet communication, and wireless communication between awireless device and multiple peripherals.

2. Background

Wireless communication systems may be designed to support various enduses. Here, one or more tradeoffs may be made in terms of coverage area,communication bandwidth, data transfer rate, ease of connectivity, powerconsumption, and other system parameters. For example, a cellulartelephone network may be optimized to provide wireless coverage over avery wide area and provide ease of connectivity. In contrast, a wirelesslocal area network such as a Wi-Fi network may be optimized to providehigh speed connectivity, at the expense of the size of the wirelesscoverage area and perhaps the ease of connectivity. A wireless body areanetwork or a wireless personal area, on the other hand, may be optimizedto provide low power consumption, which may be achieved through the useof an even smaller wireless coverage area.

As an example of the latter form of network, a wireless personal areanetwork may provide connectivity for devices in a home or a small officeor may be used to provide connectivity for devices carried by a person.In a typical scenario, a wireless personal area network may provideconnectivity for devices within a range on the order of 30 meters. Insome applications, one or more of the devices that make up a wirelesspersonal area network may be portable devices. For example, a cell phonemay communicate with a headset via a wireless personal area network suchas Bluetooth.

In general, it is desirable to reduce the power consumption of suchportable devices. For example, a device that consumes less power mayutilize a smaller battery or may require less frequent battery rechargesor battery replacements. In the former scenario, the device maypotentially be manufactured in a smaller form factor and at a lowercost. In the latter case, the device may be more convenient for a userto use or may provide a lower overall cost of ownership.

Some personal area networks such as Bluetooth (e.g., IEEE 802.15.1) andZigbee (e.g., based on IEEE 802.15.4) may employ power-down strategiesto reduce the overall power consumption of a device. For example, aftera device transmits or receives a packet, the device may power downcertain portions of the device (e.g., the radio) for a certain period oftime. Here, on the transmit side the device may remain in a low powerstate until there is another packet to send. Conversely, on the receiveside the device may awake from a low power state at regular intervals todetermine whether another device is attempting to transmit data.

It also may be desirable to employ low power devices in certain bodyarea network applications. In a typical configuration, a body areanetwork may provide connectivity between devices that are worn orcarried by a person, or are incorporated into or placed within avehicle, a room or some other relatively smaller area. Thus, a body areanetwork may provide a wireless coverage area on the order of 10 metersin some implementations. In some applications the devices that make up abody area network may be portable devices or may preferably berelatively low maintenance devices. Consequently, devices that consumerelatively small amounts of power may be advantageously employed inthese and other types of applications.

SUMMARY

A summary of sample aspects of the disclosure follows. It should beunderstood that any reference to aspects herein may refer to one or moreaspects of the disclosure.

The disclosure relates in some aspects to low power wirelesscommunication techniques for devices that communicate via a wirelessbody area network, a wireless personal area network, or some other typeof wireless communication link. In some aspects the communication maycomprise ultra-wideband communication. For example, the signaling overthe network or link may have a bandwidth on the order of 500 MHz ormore.

The disclosure relates in some aspects to impulse-based communication.In some implementations the corresponding signaling pulses may compriseultra-wideband pulses. For example, in some implementations the durationof each transmitted pulse may be on the order of 1 nanosecond or less.In some implementations the pulses also may be generated with arelatively low duty cycle. That is, the pulse repetition period may berelatively long with respect to the duration of the pulses.

The disclosure relates in some aspects to inter-pulse duty cycling.Here, duty cycling refers to reducing the power consumed by a device insome manner in between the transmission of pulses, the reception ofpulses, or both (e.g., between successive transmit and receive pulses).In some implementations power consumption is reduced by disabling (e.g.,turning off power to) one or more radio circuits (e.g., a portion of acomponent, an entire component, several components) of the device. Insome implementations power consumption is reduced by reducing afrequency of a clock signal for one or more radio circuits of thedevice.

In some aspects the pulses may be generated according to variableinter-pulse time durations. For example, the pulse repetition period maybe varied such that different sets of pulses may be separated bydifferent time durations. In some implementations the inter-pulse timedurations may be varied according to a time hopping sequence.

In some aspects the pulse repetition period may be dynamically dependenton the data encoding. For example, the pulse repetition rate associatedwith a channel may be adjusted to correspond to any change in the datarate of data output by a variable rate encoder (e.g., a source encoderor a channel encoder). Consequently, the powered-on time for inter-pulseduty cycling also may be dependent on the coding scheme. For example, adecrease in the data rate of the data from the encoder may enable theuse of a lower duty cycle for the transmitted pulses.

The disclosure relates in some aspects to charging and discharging acapacitive element according to the inter-pulse duty cycling. Forexample, the capacitive element may be charged when pulses are not beingtransmitted or received, and then discharged to power the device whenpulses are being transmitted or received. In this way, the peak currentconsumption from the battery of the device during the powered-on timesof the inter-pulse duty cycling may be better matched to the averagecurrent draw from the battery of the device.

The disclosure relates in some aspects to coexisting transmission andreception of sub-packet data over a common frequency band. For example,after the transmission of one or more pulses that comprise at least aportion of a packet, one or more pulses associated with a portion ofanother packet are received via the same frequency band. This receptionof pulses is then followed by transmission, via the same frequency band,of one or more pulses that comprise at least a portion of a packet.

The disclosure relates in some aspects to communication between awireless device (e.g., a cell phone) and two or more peripherals (e.g.,headsets). In some aspects a wireless device may multicast to two ormore peripherals via one or more wireless communication links. In someaspects a peripheral may multicast to two or more devices (e.g., awireless device and another peripheral) via one or more wirelesscommunication links. In some aspects this multicasting involvescoexisting transmission and reception of multicast-related sub-packettraffic via a common frequency band.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the disclosure willbe more fully understood when considered with respect to the followingdetailed description, appended claims and accompanying drawings,wherein:

FIG. 1 is a simplified block diagram of several sample aspects of awireless communication system;

FIG. 2 is a simplified diagram of several sample pulse waveforms;

FIG. 3 is a simplified block diagram of several sample aspects of awireless device;

FIG. 4 is a flowchart of several sample aspects of operations that maybe performed to transmit pulses;

FIG. 5 is a flowchart of several sample aspects of operations that maybe performed to receive pulses;

FIG. 6 is a flowchart of several sample aspects of operations that maybe performed to adapt the transmission of pulses to a variable codingrate;

FIG. 7 is a flowchart of several sample aspects of operations that maybe performed to provide inter-pulse duty cycling;

FIG. 8 is a flowchart of several sample aspects of operations that maybe performed to provide power from a capacitive element during apowered-on state;

FIG. 9 is a simplified diagram of several sample current flow waveforms;

FIG. 10 is a simplified diagram of a sample pulse waveform illustratingsequential transmission and reception of pulses over a common frequencyband;

FIG. 11 is a flowchart of several sample aspects of operations that maybe performed to transmit and receive sub-packets over a common frequencyband;

FIG. 12 is a flowchart of several sample aspects of operations that maybe performed to account for pulse collisions;

FIG. 13 is a simplified block diagram of several sample aspects of awireless communication system;

FIG. 14, including FIGS. 14A and 14B, are flowcharts of several sampleaspects of operations that may be performed to provide a multicastsession;

FIG. 15 is a simplified diagram of a sample waveform illustrating apossible effect of using multiple pulses to represent a bit; and

FIGS. 16-21 are simplified block diagrams of several sample aspects ofseveral wireless apparatuses.

In accordance with common practice the various features illustrated inthe drawings may not be drawn to scale. Accordingly, the dimensions ofthe various features may be arbitrarily expanded or reduced for clarity.In addition, some of the drawings may be simplified for clarity. Thus,the drawings may not depict all of the components of a given apparatus(e.g., device) or method. Finally, like reference numerals may be usedto denote like features throughout the specification and figures.

DETAILED DESCRIPTION

Various aspects of the disclosure are described below. It should beapparent that the teachings herein may be embodied in a wide variety offorms and that any specific structure, function, or both being disclosedherein is merely representative. Based on the teachings herein oneskilled in the art should appreciate that an aspect disclosed herein maybe implemented independently of any other aspects and that two or moreof these aspects may be combined in various ways. For example, anapparatus may be implemented or a method may be practiced using anynumber of the aspects set forth herein. In addition, such an apparatusmay be implemented or such a method may be practiced using otherstructure, functionality, or structure and functionality in addition toor other than one or more of the aspects set forth herein. For example,in some aspects a method of providing pulses comprises generatingencoded information, transmitting pulses based on the encodedinformation, and duty cycling between the transmissions of the pulses.In addition, in some aspects this method of providing pulses alsocomprises adapting timing of the transmission of pulses based onvariable rate encoding.

FIG. 1 illustrates sample aspects of a system 100 including severalwireless communication devices 102, 104, 106, and 108 that are adaptedto communicate with one another via one or more wireless communicationlinks (e.g., communication links 110, 112, and 114). Each of the devices102, 104, 106, and 108 respectively includes one or more signalprocessors 116, 118, 120, and 122 and an RF radio component 124, 126,128, and 130 (e.g., a wireless transceiver) to establish wirelesscommunication with the other devices.

In some implementations the devices 102, 104, 106, and 108 may form atleast a portion of a wireless body area network or a personal areanetwork. For example, the device 102 may comprise a wireless stationsuch as a cell phone, a personal data assistant, or a personalentertainment device (e.g., a music or video player). In someimplementations the devices 104, 106, and 108 may comprise peripheraldevices for the device 102. For example, the device 104 may comprise aheadset including one or more input devices 132 (e.g., a microphone) andone or more output devices 134 (e.g., a speaker). The device 106 maycomprise a medical device including one or more input devices 136 (e.g.,a sensor such as a heartbeat sensor). The device 108 may comprise awatch including one or more output devices 138 (e.g., a display). Itshould be appreciated that in other implementations the devices 102,104, 106, and 108 may comprises other types of devices and maycommunicate via other types of wireless communication links (e.g.,networks).

The devices 102, 104, 106, and 108 may send various types of data to oneanother and, in some cases, to other devices (not shown in FIG. 1). Forexample, the device 104 may generate or forward data (e.g., multimediainformation or messages) to be output by the device 104 or the device108. Similarly, the device 106 may generate data (e.g., heart rateinformation) to be output by any one of the devices 102, 104, and 108.Here, multimedia information may comprise, for example, audio, video,images, data, or some combination of two or more of these types ofinformation.

The device 102 may communicate with other devices via one or more othercommunication links (not shown). For example, the device 102 may includea local area or wide area communication processor 140 that is adapted toestablish communication with, for example, a wired or wireless accesspoint (e.g., a base station) that is associated with or providesconnectivity to another network (e.g., a cellular network, the Internet,and so on). Thus, data generated by any of the devices 102, 104, or 106may be sent to some other device (e.g., a phone or computer attached toanother network). Similarly, the other device may provide data to beoutput by any of the devices 102, 104, or 108.

As will be discussed in more detail below, the signal processors 116,118, and 120 may provide appropriate source coding-related functionality142, 144, and 146, respectively, for processing data that is to betransmitted to or was received from another device. For example, suchsource coding may involve variable rate coding, waveform coding, pulsecode modulation encoding, signal delta modulation encoding, or some typeof coding.

In some implementations the devices 102, 104, 106, and 108 maycommunicate via an impulse-based physical layer. In some aspects thephysical layer may utilize ultra-wide band pulses that have a relativelyshort length (e.g., on the order of a few nanoseconds or less) and arelatively wide bandwidth. For example, an ultra-wideband pulse may havea fractional bandwidth on the order of 20% or more, have a bandwidth onthe order of 500 MHz or more, or both.

FIG. 2 illustrates a simplified example of several pulse waveforms thatmay be generated based on, for example, information from the encoders ofFIG. 1. A waveform 202 depicts a series of pulses 204 to be transmitted.A waveform 206 depicts pulses 208 that correspond to the pulses 204 asthey may appear after passing through a bandpass filter, but beforetransmission. A waveform 210 depicts pulses 212 that correspond to thepulses 208 as they may appear at a receiver after transmission through acommunication medium. Here, the pulses 212 may be relatively wide due tomultipath delay spread that occurs as the pulses 208 pass through thecommunication medium to the receiver.

The pulses 204 are modulated based on the encoded data to be transmittedto another device. Modulation of the pulses 204 may take various formsincluding, for example, phase modulation and pulse position modulation.In addition, in some implementations pulses may be transmitted in atransmitted reference format (not shown).

In some aspects impulse-based ultra-wideband signaling may be used atvery low spectral efficiencies to provide ultra-low-power communication.In particular, in the modulation form of FIG. 2 the impulses areseparated by relatively large periods of time. For example, the duration214 of each pulse 204 may be less than 1 nanosecond (e.g., 100picoseconds) while the pulse repetition interval 216 may be on the orderof 100 nanoseconds to 10 microseconds. In such a case, circuits (e.g.,the radio front ends) of the corresponding transmitter and receiver maybe duty cycled such that they are powered on only when needed totransmit or receive pulses and are powered off the remainder of thetime.

As an example, a data rate on the order of 10 Mbits per second may besupported using 1.5 GHz of bandwidth by sending or receiving a pulseevery 100 nanoseconds. In an example where the duration of each pulse208 is on the order of 1 nanosecond, a corresponding transmitter may bepowered on less than one percent of the time. That is, the transmittermay be powered on during the time period 218 and turned off during thetime period represented by the line 220.

In addition, in an example where the duration 222 of each received pulse212 is on the order of 10 to 20 nanoseconds, the corresponding receivermay be on for less than 10 percent of the time. Here, the receiver maybe powered on during the time period 222 and turned off during the timeperiod represented by the line 224.

Through the use of inter-pulse duty cycling as illustrated in FIG. 2, areduction in power consumption may be achieved because circuitsassociated the transmitter and receiver that consume relativelysignificant amounts of power may be powered on only when the device isactually transmitting or receiving. In contrast, conventional approachessuch as Bluetooth and Zigbee rely on macroscopic duty cycling at thepacket level in an attempt to achieve relatively low average powerconsumption. That is, in these approaches the transmitter and receivercircuits may be powered on for the transmission or reception of theentire packet, thereby wasting considerable power as compared to theinter-pulse duty cycling technique taught herein.

The use of low duty cycle impulse-based signaling and inter-pulse dutycycling may be advantageously employed in conjunction with various otherfeatures. For example, in some aspects the inter-pulse time durationsmay be varied over time. For example, some implementations may employtime hopping of the pulses, whereby the transmission times of the pulsesare randomly dithered to facilitate multiple access and an ergodicprocessing gain. In some aspects the pulse repetition rate of theimpulse-based signal may be adjusted in accordance with the current datarate of data provided by a variable rate encoder. In some aspects thepeak current consumption of the device during the powered-on times ofthe inter-pulse duty cycling may be better matched to the averagecurrent draw of the device. Here, a capacitive element is charged duringthe powered-off times of the inter-pulse duty cycling and dischargedduring the powered-on times to provide power to transmit and receivepulses. In some aspects impulse-based signaling may be used to provideeffectively concurrent transmission and reception of sub-packet data viaa common frequency band. In some aspects, a wireless device maywirelessly multicast with several peripherals. These and other aspectsand potential advantages of impulse-based signaling as taught hereinwill now be described in more detail in conjunction with FIGS. 3-15.

FIG. 3 illustrates a simplified example of an apparatus 300 that may,for example, implement at least a portion of the functionality of one ormore of the wireless devices of FIG. 1. The apparatus 300 includes atransceiver 302 (e.g., similar to the radios of FIG. 1) for generatingimpulse-based signals for transmission and processing receivedimpulse-based signals. The apparatus also includes one or moreprocessors 304 and 306 (e.g., similar to a signal processor of FIG. 1)for processing data to be transmitted or for processing received data.In addition, the apparatus 300 includes one or more input devices 308and output devices 310 that may be similar to the corresponding devicesof FIG. 1. As will be discussed in more detail below, the apparatus 300also may include a state controller 312 for facilitating inter-pulseduty cycling, a power controller 314 including a charging circuit forproviding power for transmission and reception of pulses, one or morepulse timing controllers 316 for controlling the relative timing of thepulses (e.g., the inter-pulse time duration), and a coding adaptationcontroller 318 for adapting the inter-pulse time duration (e.g., thepulse repetition rate) in accordance with a coding scheme (e.g., asource coding scheme or a channel coding scheme).

Sample operations of the apparatus 300 will now be discussed in moredetail in conjunction with the flowcharts of FIGS. 4-8, 10, and 12. Forconvenience, the operations of these figures (or any other operationsdiscussed or taught herein) may be described as being performed byspecific components. It should be appreciated, however, that theseoperations may be performed by other types of components and may beperformed using a different number of components. It also should beappreciated that one or more of the operations described herein may notbe employed in a given implementation.

FIGS. 4 and 5 illustrate several sample operations that may be performedin conjunction with the transmission and reception of impulse-basedsignals, respectively. Blocks 402 and 502 relate to operations that maybe performed, for example, to establish a communication channel betweena transmitter and a receiver. Hence, these operations may be part of anassociation procedure or some other similar procedure.

The operations of blocks 402 and 502 may involve selecting variouscommunication parameters relating to transceiver operations (e.g.,performed by the processors 304 and 306) that facilitate thetransmission and reception of signals over the channel. Such operationsmay include on the transmit side, for example, source coding, MACpacketizing and formatting, channel coding, interleaving, andscrambling. Complementary operations such as descrambling,deinterleaving, channel decoding, removal of MAC framing, and sourcedecoding may be performed on the receive side.

The operations of blocks 402 and 502 also may involve selectingparameters relating to the generation of the pulses. For example, aparticular pulse repetition rate may be selected for the channel. Inaddition, in some implementations a set of timeslots may be defined fortime hopping the pulses. In this case, blocks 402 and 502 may involveselecting a time hopping sequence that defines the particular timeslotwithin which each successive pulse will appear. For example, in someimplementations a random or pseudo-random sequence may be generated andprovided to the transceiver 302.

Referring now to the transmission operations of FIG. 4, after the inputdevice 308 or some other component of the apparatus 300 providesinformation (data) to be transmitted, one or more processors 304 and 306process the information for transmission (block 404). In the example ofFIG. 3, an encoder 320 may source encode the information from the device308. In some implementations source coding relates to converting ananalog waveform to a digital waveform to facilitate transmitting theinformation over the channel. Thus, source encoding may comprise, forexample, waveform encoding, pulse code modulation encoding, or sigmadelta modulation encoding. In some implementations a source coder 320may comprise a lossless/lossy encoder.

The processor 306 may perform other transmission-related operations suchas those discussed above in conjunction with block 402. As representedby block 406, in some implementations the apparatus 300 may include achannel encoder 322 that implements a channel coding scheme wherebymultiple pulses are used to represent each bit of the information to betransmitted. An example of a coding scheme is described in more detailbelow in conjunction with FIG. 15.

The encoded information is then provided to a transmitter 324 thatgenerates and transmits modulated pulses. As represented by block 408 apulse generator 326 generates pulses based on (e.g., modulated by) theencoded information. Here, some implementations may use non-coherentmodulation techniques such as, for example, pulse position modulation oron/off keying. In contrast, some implementations may use a coherentmodulation approach such as, for example, a transmitted referencetechnique. Such modulation techniques may facilitate transmission usingan impulse generator that is followed by a passive bandpass filter. Inthis case, the transmitter may only be turned on for the active durationof the pulse. As discussed herein, such a pulse may have a duration onthe order of several nanoseconds or less than a nanosecond.

The actual position in time of each generated pulse may depend on theselected pulse repetition rate, a time hopping sequence, or some otherparameter or parameters (block 410). In some aspects the pulses aregenerated according to variable inter-pulse time durations. For example,the variable inter-pulse time durations may be based on a variable pulserepetition period, time hopping, or variable coding. Accordingly, thepulse generator 326 may generate pulses based on control signalsreceived from a pulse repetition rate controller 334 and a time hoppingsequence controller 342. As discussed below in conjunction with FIG. 6,in some implementations the pulse repetition rate may be dynamicallyadapted based on the source or channel coding. The pulses generated bythe pulse generator 324 are provided to a power amplifier 328 and abandpass filter 330, and then transmitted via an antenna 332.

Referring to FIG. 6, in some implementations the encoder 320, theencoder 322, or both, may comprise a variable-rate encoder. In such acase the encoders 320 or 322 may output data at a rate that variesdepending upon the content of the input to the encoders 320 or 322. Asan example, the encoder 320 may comprise a variable-rate voice encoder(vocoder) that encodes voice waveforms received from the input device308 (e.g., a microphone). Here, in the event the voice waveforms relateto continuous speech over a given period of time the encoder 320 mayoutput data at a full rate (e.g., 16K samples per second) for thatperiod of time. In contrast, in the event the voice waveforms relate tointermittent speech over another period of time the encoder 320 mayswitch to output data at a half rate (e.g., 8K samples per second) forthat period of time.

Accordingly, at block 602 in FIG. 6 an appropriate variable-rate codingscheme is initially selected. This operation may be performed, forexample, during an association procedure as described above inconjunction with blocks 402 and 502.

As represented by block 604, the encoder 320 receives information to beencoded from the input device 308. The encoder 320 may then select anappropriate code rate (e.g., full rate, half rate, etc.) based on thecontent of the received information (block 606). For example, the codingrate may be based on the average data rate of the incoming informationover a defined period of time. Similar operations may then be performedin conjunction with blocks 604 and 606 for the channel encoder 322.

As represented by block 608, the coding adaptation controller 318 maythen adapt the timing of the transmission of pulses based on the coderate or rates. As an example, when the encoder 320 outputs data at afull rate, the pulse repetition rate for the pulses may be defined tooutput a pulse every 200 nanoseconds. In contrast, when the encoder 320outputs data at a half rate, the pulse repetition rate for the pulsesmay be defined to output a pulse every 400 nanoseconds. To this end, thecontroller 318 may control the pulse repetition rate controller 334 thatdefines the pulse repetition rate for the pulse generator 326. Similaradaptations may be made at block 608 in conjunction with the channelencoder 322.

In a similar manner as discussed above in conjunction with FIG. 4, thetransmitter 324 generates modulated pulses in accordance with theencoded information at block 610. Then, at block 612, the transmitter324 transmits the encoded information according to the selectedtransmission timing (e.g., the variable inter-pulse time durations).

Referring now to FIG. 7, the transmission (and as will be discussedbelow the reception) of the pulses also may involve inter-pulse dutycycling. To this end, the state controller 312 may control one or morecircuits of the apparatus 300 to reduce the power consumption of theapparatus 300 when pulses are not being transmitted or received. In atypical implementation, circuits associated with the RF front end of thetransceiver 302 may be turned off when the transceiver 302 is nottransmitting or receiving pulses. Such circuits may include, forexample, a low noise amplifier, a voltage controlled oscillator, adetector, a mixer, a gain buffer, a current converter, a squarer, anintegrator, a power amplifier, and so on. In some cases several of thesecircuits may be turned off or otherwise disabled. In general, suchcircuits may consume a relatively significant amount of power ascompared to other circuits of the apparatus (most of which are notdepicted in FIG. 3).

In some implementations the state controller 312 may comprise a circuitdisabler component 336 that temporarily disables one or more circuits ofthe apparatus 300. For example, the circuit disabler 336 may cut offpower to one or more circuits (e.g., analog components) or may send asignal to a circuit that causes the circuit to, for example, disablecertain functionality. In the former case, the circuit disabler 336 maycooperate with a power controller 314 that may selectively provide powerto one or more of the circuits of the apparatus 300.

In some implementations the state controller 312 may comprise a clockrate reducer component 338. The clock rate reducer 338 may adjust theclock rate of one or more clock signals that drive one or more circuitsof the apparatus 300. Here, adjusting the clock rate may involvedecreasing the frequency of a clock signal that drives several digitalcircuits of the transceiver 324. In this way, the power consumed by thecircuit or circuits may be reduced as a result of the decrease in theclock rate. In some cases, the rate of the clock may be decreased tozero Hz (i.e., the clock is turned off)

Referring to the operations of FIG. 7, as represented by block 702 thestate controller 312 may cooperate with another component of theapparatus 300 to determine whether pulses are to be transmitted orreceived. For example, the processors 304 and 306, the transceiver 302,or the pulse timing controller 316 may provide an indication to thestate controller 312 immediately before a pulse is to be output by thetransceiver 302.

As represented by block 704, the state controller may then set theinter-pulse duty cycle state to a powered-on state. Consequently, thestate controller 312 may thereby enable any previously disabled circuits(e.g., turn on the power to the circuits) or return all of the clocks totheir normal clock rate. In the example of FIG. 2, the transmit sideoperations of block 704 may coincide with the beginning of the timeperiod 218.

As represented by block 706, the transmitter 324 may then generate andtransmit the pulse as discussed herein. Thus, in the example of FIG. 2 apulse 208 may be generated and provided to the antenna 332.

As represented by block 708, after the pulse is transmitted the statecontroller 312 switches the inter-pulse duty cycle state back to thepowered-off state. The circuit disabler 336 may thus disable theappropriate circuits and/or the clock rate reducer 338 may reduce thefrequency of one or more clocks as discussed above. In the example ofFIG. 2 the transmit side operations of block 708 may coincide with theend of the time period 218

As represented by blocks 710 and 712, the apparatus 300 is maintained inthe powered off-state until another pulse needs to be transmitted (or asdiscussed below, until a pulse needs to be received). In the eventpulses are being transmitted at the pulse repetition rate (e.g., thereis currently data to be transmitted) the duration of the powered-offstate may correspond to the time period 220 between the pulses 208 inthe example of FIG. 2. In contrast, if there is no data to betransmitted, the apparatus 300 may remain in the powered-off state untilanother pulse is to be transmitted. The operations of FIG. 7 may thus berepeated as necessary whenever pulses need to be transmitted.

On the receive side, the apparatus 300 performs operations that arecomplementary to those described above in conjunction with FIGS. 4 and7. These operations will now be discussed in more detail in conjunctionwith FIG. 5.

As discussed above, at block 502 various parameters are specified forcommunication over the channel. These parameters may include, forexample, a pulse repetition rate, a time hopping sequence if applicable,and whether the pulse timing may be adapted based on variable ratecoding.

As represented by block 504, if applicable, the timing of the receptionof the pulses may be adapted based on the code rate. This may involve,for example, receiving an indication that the data being transmitted orto be transmitted is associated with a particular code rate.

As represented by block 506, the receiver 340 receives incoming pulsesvia the antenna 332. The received pulses are provided to a bandpassfilter 344 and then to a low noise amplifier 346. A pulse processor 348may then process the pulses, as necessary, to extract (e.g., demodulate)the information represented by the pulses (block 508). As discussedabove, the pulses may be received according to variable inter-pulse timedurations.

In some implementations that utilize non-coherent modulation, thereceiver 340 may incorporate a loosely locked VCO for down-conversion.Here, the VCO may be turned off between impulses (e.g., during thepowered-off state discussed herein). In some implementations such a VCOmay not utilize a phase locked loop. Here, the non-coherence may makethe demodulation relatively insensitive to phase or frequencydifferences from one pulse to the next.

In some implementations the receiver 340 may employ a super-regenerativefront end that may function as a sub-sampling receiver. Here, thesuper-regenerative front end may sample the received signal for shortperiod of time (e.g., on the order of a few picoseconds), reusing thesingle gain stage. The super-regenerative front end may then be followedby an energy detection stage.

Referring again to FIG. 5, at block 510 the received information isprocessed by the processors 304 and 306 to provide data for the outputdevice 310. To this end, the processor 306 may comprise a channeldecoder 350 that performs channel decoding operations. In someimplementations the channel decoding operation may be similar to thosethat are discussed below in conjunction with FIG. 15. In addition, theprocessor 304 may comprise a source decoder 352. Complementary to theoperation as discussed above, the source decoder 352 may, for example,convert waveform encoded data or sigma delta modulated data to analogdata for output by the output device 310. In addition, the channeldecoder 350, the source decoder 352, or both, may comprise avariable-rate decoder.

As mentioned above, inter-pulse duty cycling also may be employed inconjunction with the reception of pulses. Referring again to FIG. 7, asrepresented by block 702 the state controller 312 may cooperate withanother component of the apparatus 300 to determine whether a pulse isto be received. For example, the processors 304 and 306, the transceiver302, or the pulse timing controller 316 may provide an indication to thestate controller 312 immediately before the expected receipt of a pulseby the transceiver 302. Here, the expected time of receipt of a pulsemay be based on the current pulse repetition rate, the current timehopping sequence if applicable, the current coding rate, defined pulsescanning intervals defined for the receiver 340, or some other criterionor criteria.

As represented by block 704, in the event a pulse is expected, the statecontroller 312 may set the inter-pulse duty cycle state to a powered-onstate. In the example of FIG. 2 the operations of block 704 for thereceive side may coincide with the beginning of the time period 222.

As represented by block 706, the receiver 340 may then process thereceived pulse as discussed herein. In the example of FIG. 2 thereceived pulse is represented by the pulse 212.

As represented by block 708, after the pulse has been received the statecontroller 312 switches the inter-pulse duty cycle state back to thepowered-off state. In the example of FIG. 2 the receive side operationsof block 708 may coincide with the end of the time period 222.

As represented by blocks 710 and 712, the apparatus 300 is maintained inthe powered off-state until another pulse is to be received (or asdiscussed below, until a pulse needs to be transmitted). In the eventpulses are being received at the pulse repetition rate (e.g., there iscurrently data to be received) the duration of the powered-off state maycorrespond to the time period 224 between the pulses 212 in the exampleof FIG. 2. In contrast, if there is no data to be transmitted, theapparatus 300 may remain in the powered off state until another pulseneeds to be received. The operations of FIG. 7 may thus be repeated asnecessary whenever pulses are to be received.

It should be appreciated that the operations of FIG. 7 are alsoapplicable to the case where a pulse is transmitted after which a pulseis received, or vice versa. For example, the inter-pulse duty cyclestate may be set to powered-on during transmission of a pulse, then setto powered-off after the transmission, and then reset to powered-on whena pulse is received.

Referring now to FIGS. 8 and 9, in some implementations a capacitiveelement may be selectively charged and discharged in accordance with theinter-pulse duty cycling to efficiently provide power for pulseprocessing. For example, the capacitive element may initially be chargedwhen the transceiver 302 is not transmitting or receiving pulses. Then,when the transceiver 302 is transmitting or receiving pulses thecapacitive element may be discharged to provide power to one or morecircuits that facilitate the transmission and reception of the pulses.Such circuits may include, for example, circuits of the transmitter 324such as the power amplifier 328 and circuits of the receiver 340 such asthe low noise amplifier 346.

In some implementations the power controller 314 of FIG. 3 may comprisea charging circuit that is adapted to selectively charge and discharge acapacitive element 354. In some aspects the charging circuit maycomprise one or more switches 356 for selectively coupling thecapacitive element 354 to a power supply 358 (e.g., a battery), a load360 (e.g., one or more transmitter or receiver circuits), or both. Insome implementations, during transmission and reception of pulses, powermay be supplied to the load 360 from both the capacitive element 354 andthe power supply 358. Hence, the charging circuit may be configured(e.g., the switch or switches 356 actuated) in a manner that facilitatesproviding power from multiple sources to one or more circuits.

Referring now to the operations of FIG. 8, as represented by block 802the charging circuit may initially be configured so that the capacitiveelement 354 does not supply power to the load 360 when the transmitter324 is not transmitting pulses and the receiver 340 is not receivingpulses. In addition, the charging circuit may initially be configured sothat the capacitive element 354 is charging for at least a portion of atthis time. In FIG. 2 this scenario may coincide with the time periods220 and 224 (e.g., the power-off state of the state controller 312).

As represented by block 804, at some point in time the apparatus 300determines that a pulse needs to be transmitted or received. As aresult, the apparatus 300 may change the duty cycle state to thepowered-on state (block 806). The apparatus 300 may perform theseoperations, for example, as discussed above in conjunction with FIG. 7.

As represented by block 808, the charging circuit may then provide powerto the designated circuits during the transmission or reception ofpulses (block 810). For example, in some implementations the switch(es)356 may decouple the capacitive element 354 from being charged by thepower supply 358 and couple the capacitive element 354 to providecurrent to the load 360. It should be appreciated that a variety ofcircuits may be used to couple the capacitive element 354 to powersupply 358 and to the load 360 to accomplish this operation or othersimilar operations.

FIG. 9 depicts several waveforms that serve to illustrate relativecurrent draws between the states of blocks 802 and 808. A waveform 902illustrates an example of current draw at the transmitter 324 or thereceiver 340. A waveform 904 illustrates charge current (top half of thewaveform) and discharge current (bottom half of the waveform) for thecapacitive element 354. A waveform 906 illustrates an example of currentdraw from the power supply 358. It should be appreciated that thewaveforms of FIG. 9 are presented in a simplified manner to highlightthe basic concepts herein. In practice, the actual current flows maydiffer significantly from those shown in the figure.

Levels 908, 910, and 912 relate to current flow during a powered-offstate. In this case, the transmitter 324 or the receiver 340 may bedrawing a relatively small amount of current as represented by the level908. In addition, the capacitive element 354 may be charging at thistime as represented by the level 910. Also, the power supply may beproviding a relatively average amount of power to the apparatus 300 asrepresented by the level 912.

The levels 914, 916, and 918 relate to current flow during a powered-onstate that corresponds to a period of time between the dashed lines 920Aand 920B. In this case, the transmitter 324 or the receiver 340 may bedrawing a relatively significant amount of current as represented by theraised portion of the waveform 914. The capacitive element 354 may thusbe discharging at this time as represented by a dipped portion of thewaveform 916. That is, current stored on the capacitive element 354during a powered-off state may now be provided to the transmitter 324 orthe receiver 340. In addition, the power supply 358 also may beproviding additional output current to the transmitter 324 or thereceiver 340 as represented by the waveform portion 918.

It should be appreciated that the operation of the capacitive element354 may serve to reduce the amount of peak power supplied by the powersupply 358. For example, a battery may operate less efficiently at peakpower levels (e.g., resulting in a disproportionately shorter lifetime).Accordingly, the operation of the capacitive element 354 may reduce theoverall power consumption of the apparatus 300 by reducing the peakcurrent load on the power supply 358.

The charging circuit may be implemented in various ways to provide anappropriate amount of power during the powered-on state. For example, insome implementations a sufficient charge is placed on the capacitiveelement 354 during the powered-off state to enable the power supply 358to supply, during transmission or reception of one or more pulses, anamount of current that is not substantially more than the averagecurrent drawn from the power supply 358. In some implementations theamount of current referred to above is at most 20% more than the averagecurrent drawn from the power supply 358. It should be appreciated thatother percentages or amounts may be employed in other implementations.

In some implementations a sufficient charge is placed on the capacitiveelement 354 during a powered-off state to enable the power supply 358 tosupply, during transmission or reception of one or more pulses, anamount of current that is substantially less than a peak currentassociated with the transmission or reception of one or more pulses.Here, the peak current may comprise, for example, the current drawn bythe transmitter 324 during transmission or the receiver 342 duringreception. In some implementations the amount of current referred toabove is at least 20 percent less than the peak current. It should beappreciated that other percentages or amounts may be employed in otherimplementations.

Referring again to FIG. 8, after the pulses are transmitted or received,the duty cycle state may be set back to the powered-off state (block812). Accordingly, as represented by block 814 the capacitive elementmay be reconfigured to charge and to not supply power as discussed abovein conjunction with block 802. As represented by blocks 816 and 818 theabove operations may be repeated, as necessary, to charge and dischargethe capacitive element 354 in accordance with the inter-pulse dutycycling. Here, it should be appreciated that the above techniques alsoapply in the event the transceiver operations switch between thetransmission and reception of pulses. For example, after a pulse istransmitted the capacitive element may charge during the powered-offstate, and then be discharged during a subsequent receive operation.

Referring now to FIGS. 10, 11, and 12, the disclosure also relates insome aspects to using impulse-based signaling to transmit and receiveportions of packets over a common frequency band in a substantiallyconcurrent manner. Here, packets may comprise sets of data that arerepeatedly delineated in some manner for transmission. For example, apacket may be defined by a formal protocol header, a preamble, or someother suitable delineation technique.

FIG. 10 illustrates a series of pulses 1000 generated within a givenfrequency band as they may appear over a given period of time. Duringthe first portion of the time period one or more pulses may betransmitted. FIG. 10 illustrates the last transmitted pulse 1002 fromthe first portion of the time period. During a later portion of the timeperiod one or more pulses 1004 may be received. Then, during an evenlater portion of the time period one or more pulses may again betransmitted. FIG. 10 illustrates the first transmitted pulse 1006 fromthe latest portion of the time period. The ellipses of FIG. 10illustrate that additional sets of pulses may be transmitted andreceived over time.

Here, one or more of the sets of pulses 1002, 1004, and 1006 maycomprise a portion of the packet. That is, a packet to be transmittedmay be divided up into different portions and each portion of the packetmay be transmitted as a set of one or more pulses. Similarly, a packetto be received may have been divided up into different portions by aremote transmitter whereby the remote transmitter transmits each portionof its packet as a set of one or more pulses. As illustrated in FIG. 10,the transmission and reception of these different sets of pulsesassociated with different sub-packets may be interspersed in time over agiven time period (e.g., by alternately transmitting and receivingportions of the packets). For example, alternately transmitting a pulseof a packet, receiving a pulse of a different packet, transmitting thenext pulse of the first packet, and so forth. From a macro scale itappears that the transceiver is transmitting and receiving a packetsimultaneously in the same frequency band.

The particular grouping of sets of pulses (e.g., as illustrated in FIG.10) may depend on various factors. For example, in some applications,rather than transmit a relatively large pulse that may negatively impactpeak power requirements, it may be desirable to instead represent thatinformation as a series of smaller pulses that are transmitted insuccession. In addition, the transmit pulses may be transmitted at adifferent pulse repetition rate than the receive pulses, or vice versa.This may be the result of, for example, a different data rate or adifferent processing gain. In some implementations the number of pulsestransmitted in succession may be on the order of 100 pulses or less orthe maximum duration of a set of pulses (e.g., transmit pulses) may beon the order of 20 microseconds or less. In addition, to maintain asufficiently low duty cycle (e.g., as discussed above in conjunctionwith FIG. 2), in some implementations the duration of a given pulse maybe 20 nanoseconds or less.

In some implementations the transmit pulses 1002 and 1006 may betransmitted via one defined code channel within the defined frequencyband and the received pulses 1004 received via another defined codechannel within the same frequency band. Here, these different codechannels may be defined by different pulse repetition periods, differenttime hopping sequences, different scrambling codes, different modulationschemes, some other parameter, or some combination of two or more ofthese parameters.

In some implementations the pulses transmitted and received by a givendevice (e.g., as shown in FIG. 10) may be destined for one or more otherdevices and received from one or more other devices. For example, thesets of transmitted pulses may be associated with a multicast streamthat is received by different devices. Alternatively, different sets oftransmitted pulses may be sent to different devices (e.g., usingdifferent code channels). Likewise, different sets of received pulsesmay have been transmitted by different devices (e.g., using differentcode channels).

FIG. 11 illustrates several sample operations that may be performed totransmit and receive sub-packets. Block 1102 represents the commencementof impulse-based packet transmission over a given frequency band. Asdiscussed herein the impulse based signaling scheme may optionallyemploy time hopping.

As represented by block 1104, the processor 306 (FIG. 3) may formatinformation (e.g., packet data) for transmission. For example, in someimplementations the processor 306 may encode the information to betransmitted by generating a series of symbols representative of thecurrent portion of the packet to be transmitted. Here, each symbol maybe representative of one or more bits of information from thissub-packet. It should be appreciated that in some implementationssymbols representative of the data to be transmitted may be generated bya modulation scheme (e.g., with or without prior encoding). In anyevent, the pulse generator 326 may generate one or more pulsesrepresentative of each symbol. Hence, each pulse set of FIG. 10 mayrepresent a portion of a symbol, an entire symbol, or several symbols.

As represented by block 1106, the transceiver 302 also may commencesubstantially concurrent reception of packets over the selectedfrequency band and, optionally, time hopping. As represented by block1108, in an apparatus 300 that employs inter-pulse duty cycling astaught herein, the duty cycling state may be changed to a powered-onstate.

As represented by block 1110 the transmitter 324 transmits a first setof a least one pulse (e.g., pulse 1002 in FIG. 10). As discussed hereinthe first pulse set may comprise at least a portion of a packet. As willbe discussed in more detail below in conjunction with FIGS. 13 and 14,in some implementations coexisting transmission and reception ofsub-packets may be employed in conjunction with multicasting operations.As represented by block 1112, after the first pulse set has beentransmitted, the duty cycling state may be changed back to a powered-offstate until the next transmission or reception (e.g., at block 1114).

As represented by block 1114, the receiver 340 receives at least onepulse (e.g., pulses 1004) over the common frequency band. Here, itshould be appreciated that the same radio front-end may be used forreceiving the at least one pulse as was used for transmitting the firstpulse set at block 1110. As mentioned above in conjunction with block1110, this reception of pulses may be related to a multicastingoperation. As represented by block 1116, after the at least one pulsehas been received, the duty cycling state may be changed back to apowered-off state until the next transmission or reception (e.g., atblock 1118).

As represented by block 1118 the transmitter 324 transmits a second setof a least one pulse (e.g., pulse 1006). Again, this second pulse setmay comprise at least a portion of a packet. As represented by block1120, after the second pulse set has been transmitted, the duty cyclingstate may be changed back to a powered-off state until the nexttransmission or reception.

As represented by block 1122, the above operations may be repeated asnecessary to repeatedly transmit and receive sub-packets over the commonfrequency band. Although the discussion above referred primarily to thetransmission and reception of sub packets, in some aspects one or moreof the sets of pulses may comprise an entire packet or more than anentire packet. As represented by block 1124, the at least one pulsereceived at block 1114 may be processed (e.g., decoded) as discussedherein.

Referring now to FIG. 12, in some aspects provisions may be made toaccount for collisions that may occur or could potentially occur betweena transmit pulse and a receive pulse. That is, at some points in time apulse may be transmitted at the same or substantially the same point intime as a pulse is being received.

As represented by block 1202, an error correction processor component362 may identify a collision of transmit and receive pulses. Thisidentification may be made after a collision has happened, as acollision is happening, or in some aspects may be predicted based onknown or expected transmission and reception times.

As represented by block 1204, the component 362 may adjust the errorcorrection being used for the channel based on identification of thecollision. Here, whenever a collision is detected, this information maybe fed into the error correction scheme. The error correction scheme maythen be configured to take some action whenever there is a collision.For example, in some implementations the component 362 may mark thecorresponding transmitted or received pulse as an erasure (e.g., in aconvolutional code, mark the bit with a zero confidence level). In atypical implementation the component 362 may mark the transmit pulse asan erasure since this may be easier than having a remote receiverattempt to determine whether or not there was a transmission.

As represented by block 1206, in some aspects the component 362 maydetermine a confidence level associated with received pulses. Forexample, some applications may employ error correction schemes whereby aconfidence level may be assigned to the received data, indicative of adegree to which the received data accurately represents the informationthat was transmitted by the remote transmitter. Here, depending upon theerror correction scheme employed and the characteristics of the channel,the confidence level may be relatively high even though one or morepulses may have been corrupted during transmission through the channel.

As represented by block 1208, the component 362 may then determine basedon the confidence level whether it needs to receive the pulse inquestion (e.g., associated with a collision or potential collision). Forexample, if there is a high level of confidence regarding the receivedinformation it may not be necessary to receive this pulse since thepulse would simply be redundant information. Thus, in this case thecomponent 362 may simply ignore the received pulse. In addition, in theevent the received pulse would arrive at a time that the transmitter 324wishes to transmit a pulse, the transceiver 302 may be allowed totransmit the pulse anyway. In contrast, if the channel is relativelynoisy or if the receiver 340 is having difficulty receiving theinformation for some other reason, the component 362 may determine thatit needs to try to decode the information associated with the pulse.From the above it should be appreciated that the component 362 maydynamically determine the action to be taken in the event of a collisionor potential coalition.

Referring now to FIG. 13, in some aspects the disclosure relates tocommunication between a wireless device (e.g., a cell phone, a personalentertainment device such as an MP3 player or a video player, a personaldata assistant, a computer, and so on) and multiple peripherals (e.g.,headsets) via several wireless communication links. In some aspectsthese components multicast via the wireless communication links. Forexample, a wireless device may directly establish a multi-way conferencecall between itself and several headsets via wireless links. In someaspects the wireless links may utilize impulse-based signaling as taughtherein. In this case, the devices also may support inter-pulse dutycycling to save power as discussed herein.

In the example of FIG. 13 a wireless communication system 1300 includesa wireless device 1302 and two peripherals 1304 and 1306. It should beappreciated, however, that a given implementation may incorporate moreperipherals. The wireless device 1302 may communicate with a cellularnetwork via a wide area network component 1308. In addition, thewireless device 1302 may establish the wireless communication links withthe peripherals 1304 and 1306 via a transmitter 1310 and a receiver1312. Similarly, the peripherals 1304 and 1306 include correspondingtransmitters 1314A and 1314B and receivers 1316A and 1316B,respectively.

Each of the devices 1302, 1304, and 1306 in FIG. 13 also may includevarious components for communicating with one another or some otherdevice (not shown). For example, the device 1302 includes speaker 1318,a microphone 1320, a control device (e.g., for adjusting volume andjoining a call) 1322, a baseband processor 1324, and a source codingcomponent 1326. The device 1304 includes speaker 1328A, a microphone1330A, a control device 1332A, a baseband processor 1334A, and a sourcecoding component 1336A. Similarly, the device 1306 includes speaker1328B, a microphone 1330B, a control device 1332B, a baseband processor1334B, and a source coding component 1336B.

Sample operations of the devices 1302, 1304, and 1306 will now bediscussed in conjunction with the flowcharts of FIG. 14. As representedby block 1402 in FIG. 14A initially the wireless device 1302 establishesthe wireless communication links with the peripherals 1304 and 1306. Insome aspects this may involve temporarily pairing each peripheral 1304and 1306 with the wireless device 1302 for the duration of acommunication session (e.g., a phone call). In some implementations theperipherals 1304 and 1306 may be synchronized to the wireless device1302.

In some aspects multicasting may be implemented using a wirelessmulticast link and wireless unicast links or only using wireless unicastlinks. For example, in some implementations a multicast link may beestablished to send multicast data from the wireless device 1302 to bothof the peripherals 1304 and 1306. In this case, separate unicast linksmay then be established to send data from each peripheral 1304 and 1306to the wireless device 1302. Conversely, in some implementationsseparate unicast links, rather than a multicast link, may be establishedto send multicast data from the wireless device to each of theperipherals 1304 and 1306.

In a sample use case, a conference call may be established using asingle wireless device (e.g., a cell phone) and multiple headsets. Insome implementations, the cell phone may use a multicast link (orunicast links) to send multicast data to the headsets. The headsets inturn may send data back to the cell phone via separate unicast links (ormulticast links). This data may include, for example, microphone dataand side tone data. The cell phone also may receive data from othersources such as, for example, data from a wide area network (e.g., anincoming signal associated with a call over a cellular network). Thecell phone may then mix the incoming data (e.g., the microphone data,side tone data, etc.) and send the mixed data to the devices (e.g., theperipherals and the wide area network). Thus, the cell phone maymulticast the microphone data (as mixed with other audio data, ifapplicable) to the headsets via one or more wireless links.

In some implementations the wireless communication links may utilizeimpulse-based signaling as taught herein. For example, each unicast linkmay employ a low duty cycle, pulse time hopping, inter-pulse dutycycling, or any other technique taught herein. In addition, themulticast-related links may be realized using sub-packet transmissionand reception via a comment frequency band as described herein (e.g., atFIGS. 10-12).

As represented by block 1404 in FIG. 14A, one of the peripherals 1304 or1306 sends information to the wireless device 1302. As discussed abovethis may be accomplished via a wireless unicast link, or via onedirection of a sub-packet transmit and receive link (e.g., pulses 1004of FIG. 10).

As represented by block 1406, the wireless device 1302 receives theinformation from the peripheral(s) and, in some cases, from some othersource or sources. Here, another source may include another one of theperipherals 1304 or 1306 or some other communication device associatedwith the current communication session (not shown). For example, in thecase of a conference call the wireless device 1302 may be connected toanother caller via a cellular network.

As represented by block 1408, the wireless device 1302 processes theinformation received from the peripheral(s) and any other source device.For example, the wireless device 1302 (e.g., the baseband processor1324) may mix the received information (e.g., audio signals).

As represented by block 1410, the wireless device 1302 transmits theprocessed information to the peripherals 1304 and 1306 and, ifapplicable, any other devices associated with the current communicationsession. As mentioned above, in some implementations the wireless device1302 may transmit the processed information as a single multicast streamvia a single wireless communication link. In this case, each peripheralwill receive the stream from the multicast link. In otherimplementations the wireless device 1302 may transmit the processedinformation as multiple unicast streams via multiple wirelesscommunication links. In still other implementations the wireless device1302 may transmit via one direction of a sub-packet transmit and receivelink (e.g., pulses 1002 and 1006 of FIG. 10).

As represented by block 1412, the peripherals 1304 and 1306 receive theprocessed information from the wireless device 1302. The peripherals1304 and 1306 then process the received information as necessary (block1414).

As mentioned above a peripheral (e.g., peripheral 1304) may transmitvarious types of data (i.e., information) and may transmit the data invarious ways. Several additional sample operations of a peripheral willnow be treated in conjunction with the flowchart of FIG. 14B.

As represented by block 1420, the peripheral may obtain data to betransmitted from one or more data sources. For example, the peripheralmay obtain data from its microphone. In addition, the peripheral mayreceive data from the wireless device 1302, from one or more otherperipherals, from some other source, or from some combination of thesesources. As an example, the peripheral 1304 may receive microphone datafrom the peripheral 1306 via a wireless link.

As represented by block 1422, the peripheral may process the data itobtained in some manner to facilitate transmitting the data. Forexample, in some implementations the peripheral (e.g., the basebandprocessor 1334A) may mix the data (e.g., the microphone data frommultiple sources).

As represented by block 1424, the peripheral may then transmit theprocessed data to an appropriate destination or destinations. In someimplementations the peripheral may transmit the data to another device(e.g., the wireless device 1302 or the peripheral 1306) via a unicastlink. In some implementations the peripheral may transmit the data toseveral devices (e.g., the wireless device 1302 and the peripheral 1306)via several unicast links. In some implementations the peripheral maytransmit the data to several devices (e.g., the wireless device 1302 andthe peripheral 1306) via a multicast link. Thus, in this case the cellphone may multicast some or all of the microphone data from multipleheadsets (as mixed with other audio data, if applicable) to the headsetsor other devices via the wireless links.

Referring now to FIG. 15, as mentioned above in some implementations adevice that utilizes pulse-based ultra-wideband communication may employvarious coding techniques to improve the reliability ofdata-transmission over a channel. In some aspects, the disclosurerelates to using multiple pulses per bit to provide improvedinterference performance in a non-coherent ultra-wideband system.

In ultra-wideband systems with non-coherent receivers, a single pulseper bit has traditionally been used to minimize non-coherent combininglosses and obtain the best performance in noise-limited channels. Forexample, a typical non-coherent ultra-wideband (“UWB”) receiver (e.g.,pursuant to IEEE 802.15.4a) and implementations that accommodate suchreceivers may use a very high rate (close to rate one) coded pulses incombination with time-hopping diversity.

Due to the presence of noise-noise cross terms in a non-coherentreceiver, using more than one pulse per bit may lead to an effectiveloss in the E_(b)/N_(o) requirement. As an example, in a binary pulseposition modulation (“BPPM”) UWB system, for every doubling of thespread factor, there is approximately 1 dB of loss in E_(b)/N_(o) at thetarget un-coded BER=10⁻³. This means that every doubling of the spreadfactor delivers only 2 dB of spreading gain, instead of 3 dB in the caseof a coherent receiver. Due to this non-coherent combining loss,conventional designs use a high rate code (e.g., a Reed-Solomon code)leading to a pulse per bit value close to one.

However, more than one pulse per bit may be advantageously employed whenthe system is interference-limited. To illustrate this point, an exampleof a hypothetical system will described. In this hypothetical system,the following condition are defined for the transmitter: 1) The systemdoes not use any coding other than repetition (e.g., PN sequence) basedspreading; 2) The parameters are chosen such that there is nointer-pulse, inter-pulse position hypothesis, or inter-symbolinterference issues within a link; and 3) Any time-hopping sequencechosen is i.i.d. uniform distributed within and between users over thepossible pulse locations. In addition, the following parameters aredefined: 1) The system may produce N non-overlapping binary pulseposition modulated symbol locations per un-coded bit. Here, each BPPMsymbol consists of two non-overlapping positions denoting ‘1’ and ‘0’.Hence, this means that there are 2N pulse locations in total; and 2) Thespreading code length is M. Then, each pulse may have T=N/M possibletime-hopping locations. Finally, the following conditions are definedfor the receiver: 1) The integrator captures all the energy in the BPPMsymbol location; and 2) BPPM detection uses a hard detector. This meansthat if energy at pulse position corresponding to ‘1’ is larger thanthat in ‘0’, the detector decides in favor of ‘1’.

Next, it is assumed that the link of interest is operating under thepresence of a much stronger interferer. Since each user is assumed tohave i.i.d. uniform time-hopping sequence, the probability that a pulsesent by the interferer falls in one of the two time hopped BPPMhypothesis locations corresponding to the user of interest may be 1/T.The interference may thus help or hinder accurate detection of a pulsedepending on where the interfering pulses fall in one of the two timehopped BPPM hypothesis locations. Hence, the average pulse error ratemay be 1/(2 T).

Under the above conditions, for odd values of M, the BER error floor maybe: $\begin{matrix}{{BER}_{Floor} = {\sum\limits_{i = 0}^{\lfloor{M/2}\rfloor}\quad{{C( {M,i} )}( \frac{1}{2\quad T} )^{M - i}( {1 - \frac{1}{2\quad T}} )^{i}}}} & {{EQUATION}\quad 1}\end{matrix}$

This leads to a trade-off between the spreading code length (M) and theBER floor under interference. For N=50, an example of this trade-off isplotted in FIG. 15. This plot illustrates that the behavior of thesystem under interference may benefit from a large number of pulses perbit (e.g., five or more). Hence, multiple pulses per bit may beadvantageously employed in a time hopped non-coherent system to improveperformance in an interference-limited region.

From the above it should be appreciated that impulse-based signaling astaught herein may be advantageously employed in an apparatus havingultra-low power requirements. In some implementations the teachingsherein may be employed to achieve spectral efficiencies of less than 0.1bit/second/Hz. Such techniques may be advantageously employed forshort-range communication to, for example, send data between a cellphone and a wristwatch, where the wrist watch may typically consume anamount of power on the order of a few microwatts. Similarly, thesetechniques may be employed to send data between a cell phone and anin-ear headset (e.g., similar to a hearing aid), where the headset maytypically consume an amount of power on the order of a few milliwatts.

A wireless device may include various components that perform functionsbased on signals that are transmitted by or received at the wirelessdevice. For example, a headset may include a transducer adapted toprovide an audible output based on: pulses that are received via awireless link, decoded information, one or more received pulses, orprocessed information. A watch may include a display adapted to providea visual output based on: pulses that are received via a wireless link,decoded information, one or more received pulses, or processedinformation. A medical device may include a sensor adapted to generatesensed data: to be transmitted by a transmitter, for transmission via awireless link, to provide one or more transmitted pulses, or to betransmitted to a cell phone.

A wireless device may communicate via one or more wireless communicationlinks that are based on or otherwise support any suitable wirelesscommunication technology. For example, in some aspects a wireless devicemay associate with a network. In some aspects the network may comprise abody area network or a personal area network (e.g., an ultra-widebandnetwork). In some aspects the network may comprise a local area networkor a wide area network. A wireless device may support or otherwise useone or more of a variety of wireless communication protocols orstandards including, for example, CDMA, TDMA, OFDM, OFDMA, WiMAX, Wi-Fi,and other wireless technologies. Similarly, a wireless device maysupport or otherwise use one or more of a variety of correspondingmodulation or multiplexing schemes. A wireless device may thus includeappropriate components (e.g., air interfaces) to establish andcommunicate via one or more wireless communication links using the aboveor other wireless communication technologies. For example, a device maycomprise a wireless transceiver with associated transmitter and receivercomponents (e.g., transmitter 326 and the receiver 340) that may includevarious components (e.g., signal generators and signal processors) thatfacilitate communication over a wireless medium.

As mentioned above, in some aspects a wireless device may communicatevia ultra-wideband pulses. In some aspects each of the ultra-widebandpulses may have a bandwidth on the order of 1-2 GHz. In some aspectseach of the ultra-wideband pulses may have a frequency band (i.e.,frequency range) within a range of approximately 6 GHz to 10 GHz. Insome aspects each of the ultra-wideband pulses may have a frequency bandwithin a range of approximately 7.25 GHz to 9 GHz. In some aspects eachof the ultra-wideband pulses may have a time duration on the order of 20nanoseconds of less.

The teachings herein may be incorporated into (e.g., implemented withinor performed by) a variety of apparatuses (e.g., devices). For example,one or more aspects taught herein may be incorporated into a phone(e.g., a cellular phone), a personal data assistant (“PDA”), anentertainment device (e.g., a music or video device), a headset (e.g.,including a headphones, an earpiece, a microphone, or some combinationof two or more of these devices), a microphone, a medical device (e.g.,a biometric sensor, a heart rate monitor, a pedometer, an EKG device,etc.), a user I/O device (e.g., a watch, a remote control, a lightswitch, a keyboard, a mouse, etc.), a tire pressure monitor, a computer,a point-of-sale device, an entertainment device, a hearing aid, aset-top box, or any other suitable device.

These devices may have different power and data requirements. In someaspects, the teachings herein may be adapted for use in low powerapplications (e.g., through the use of a impulse-based signaling schemeand low duty cycle modes) and may support a variety of data ratesincluding relatively high data rates (e.g., through the use ofhigh-bandwidth pulses).

In some aspects a wireless device may comprise an access device (e.g., aWi-Fi access point) for a communication system. Such an access devicemay provide, for example, connectivity to another network (e.g., a widearea network such as the Internet or a cellular network) via a wired orwireless communication link. Accordingly, the access device may enableanother device (e.g., a Wi-Fi station) to access the other network orsome other functionality. In addition, it should be appreciated that oneor both of the devices may be portable or, in some cases, relativelynon-portable.

The components described herein may be implemented in a variety of ways.Referring to FIGS. 16-21, apparatuses 1600, 1650, 1700, 1750, 1800,1900, 2000, 2050, 2100, and 2150 are represented as a series ofinterrelated functional blocks that may represent functions implementedby, for example, one or more integrated circuits (e.g., an ASIC) or maybe implemented in some other manner as taught herein. As discussedherein, an integrated circuit may include a processor, software, othercomponents, or some combination thereof.

As shown in FIG. 16, the apparatus 1600 may include one or more modules1602, 1604, 1606, 1608, 1610, 1612, and 1614 that may perform one ormore of the functions described above with regard to various figures.For example, an ASIC for generating encoded information 1602 maycorrespond to, for example, component 320 discussed above. An ASIC fortransmitting 1604 may correspond to, for example, component 324discussed above. An ASIC for duty cycling 1606 may correspond to, forexample, component 312 discussed above. An ASIC for source encoding 1608may correspond to, for example, component 320 discussed above. An ASICfor waveform encoding 1610 may correspond to, for example, component 320discussed above. An ASIC for sigma delta modulation encoding 1612 maycorrespond to, for example, component 320 discussed above. An ASIC forproviding a time hopping sequence 1614 may correspond to, for example,component 342 discussed above.

The apparatus 1650 may include one or more modules 1652, 1654, 1656,1658, 1660, 1662, and 1664 that may perform one or more of the functionsdescribed above with regard to various figures. For example, an ASIC forreceiving 1652 may correspond to, for example, component 340 discussedabove. An ASIC for duty cycling 1654 may correspond to, for example,component 312 discussed above. An ASIC for decoding 1656 may correspondto, for example, component 352 discussed above. An ASIC for sourcedecoding 1658 may correspond to, for example, component 352 discussedabove. An ASIC for waveform decoding 1660 may correspond to, forexample, component 352 discussed above. An ASIC for sigma deltamodulation decoding 1662 may correspond to, for example, component 352discussed above. An ASIC for providing a time hopping sequence 1664 maycorrespond to, for example, component 342 discussed above.

As shown in FIG. 17, the apparatus 1700 may include one or more modules1702, 1704, 1706, and 1708 that may perform one or more of the functionsdescribed above with regard to various figures. For example, an ASIC fortransmitting 1702 may correspond to, for example, component 324discussed above. An ASIC for duty cycling 1704 may correspond to, forexample, component 312 discussed above. An ASIC for providing a randomsequence 1706 may correspond to, for example, component 342 discussedabove. An ASIC for generating encoded information 1708 may correspondto, for example, component 320 discussed above.

The apparatus 1750 may include one or more modules 1752, 1754, 1756, and1758 that may perform one or more of the functions described above withregard to various figures. For example, an ASIC for receiving 1752 maycorrespond to, for example, component 340 discussed above. An ASIC forduty cycling 1754 may correspond to, for example, component 312discussed above. An ASIC for providing a random sequence 1756 maycorrespond to, for example, component 342 discussed above. An ASIC fordecoding 1758 may correspond to, for example, component 352 discussedabove.

As shown in FIG. 18, the apparatus 1800 may include one or more modules1802, 1804, 1806, 1808 that may perform one or more of the functionsdescribed above with regard to various figures. For example, an ASIC forusing power 1802 may correspond to, for example, component 302 discussedabove. An ASIC for duty cycling 1804 may correspond to, for example,component 312 discussed above. An ASIC for charging 1806 may correspondto, for example, component 314 discussed above. An ASIC for varying 1808may correspond to, for example, component 316 discussed above.

The apparatus 1900 may include one or more modules 1902, 1904, 1906,1908, and 1910 that may perform one or more of the functions describedabove with regard to various figures. For example, an ASIC fortransmitting 1902 may correspond to, for example, component 324discussed above. An ASIC for receiving 1904 may correspond to, forexample, component 340 discussed above. An ASIC for error correcting1906 may correspond to, for example, component 362 discussed above. AnASIC for duty cycling 1908 may correspond to, for example, component 312discussed above. An ASIC for varying 1910 may correspond to, forexample, component 316 discussed above.

As shown in FIG. 20, the apparatus 2000 may include one or more modules2002 and 2004 that may perform one or more of the functions describedabove with regard to various figures. For example, an ASIC forcommunicating 2002 may correspond to, for example, component 302discussed above. An ASIC for processing 2004 may correspond to, forexample, component 304 and/or component 306 discussed above.

The apparatus 2050 may include one or more modules 2052, 2054, and 2056that may perform one or more of the functions described above withregard to various figures. For example, an ASIC for receiving 2052 maycorrespond to, for example, component 340 discussed above. An ASIC forprocessing 2054 may correspond to, for example, component 304 and/orcomponent 306 discussed above. An ASIC for transmitting 2056 maycorrespond to, for example, component 324 discussed above.

As shown in FIG. 21, the apparatus 2100 may include one or more modules2102 and 2104 that may perform one or more of the functions describedabove with regard to various figures. For example, an ASIC formulticasting 2102 may correspond to, for example, component 302discussed above. An ASIC for processing 2104 may correspond to, forexample, component 304 and/or component 306 discussed above.

The apparatus 2150 may include one or more modules 2152, 2154, and 2156that may perform one or more of the functions described above withregard to various figures. For example, an ASIC for receiving 2152 maycorrespond to, for example, component 340 discussed above. An ASIC forprocessing 2154 may correspond to, for example, component 304 and/orcomponent 306 discussed above. An ASIC for transmitting 2156 maycorrespond to, for example, component 324 discussed above.

As noted above, in some aspects these components may be implemented viaappropriate processor components. These processor components may in someaspects be implemented, at least in part, using structure as taughtherein. In some aspects a processor may be adapted to implement aportion or all of the functionality of one or more of these components.In some aspects one or more of the components represented by dashedboxes are optional.

As noted above, the apparatuses of FIGS. 16-21 may comprise one or moreintegrated circuits that provide the functionality of the correspondingcomponents. For example, in some aspects a single integrated circuit mayimplement the functionality of the illustrated components, while inother aspects more than one integrated circuit may implement thefunctionality of the illustrated components.

In addition, the components and functions represented by FIGS. 16-21, aswell as other components and functions described herein, may beimplemented using any suitable means. Such means also may beimplemented, at least in part, using corresponding structure as taughtherein. For example, in some aspects means for generating encodedinformation may comprise an encoder, means for transmitting may comprisea transmitter, means for duty cycling may comprise a state controller,means for source encoding may comprise a source encoder, means forwaveform encoding may comprise a waveform encoder, means for sigma deltamodulation encoding may comprise a sigma delta modulation encoder, meansfor providing a time hopping sequence may comprise a time hoppingsequence controller, means for receiving may comprise a receiver, meansfor decoding may comprise a decoder, means for source decoding maycomprise a source decoder, means for waveform decoding may comprise awaveform decoder, means for sigma delta modulation decoding may comprisea sigma delta modulation decoder, means for providing a random sequencemay comprise a time hopping sequence controller, means for using powermay comprise a transceiver, means for charging may comprise a chargingcircuit, means for error correcting may comprise an error correctionprocessor, means for communicating may comprise a transceiver, means forprocessing may comprise a processor, means for multicasting may comprisea transceiver, and means for varying may comprise a pulse timingcontroller. One or more of such means also may be implemented inaccordance with one or more of the processor components of FIGS. 16-21.

Those of skill in the art would understand that information and signalsmay be represented using any of a variety of different technologies andtechniques. For example, data, instructions, commands, information,signals, bits, symbols, and chips that may be referenced throughout theabove description may be represented by voltages, currents,electromagnetic waves, magnetic fields or particles, optical fields orparticles, or any combination thereof.

Those of skill would further appreciate that any of the variousillustrative logical blocks, modules, processors, means, circuits, andalgorithm steps described in connection with the aspects disclosedherein may be implemented as electronic hardware (e.g., a digitalimplementation, an analog implementation, or a combination of the two,which may be designed using source coding or some other technique),various forms of program or design code incorporating instructions(which may be referred to herein, for convenience, as “software” or a“software module”), or combinations of both. To clearly illustrate thisinterchangeability of hardware and software, various illustrativecomponents, blocks, modules, circuits, and steps have been describedabove generally in terms of their functionality. Whether suchfunctionality is implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem. Skilled artisans may implement the described functionality invarying ways for each particular application, but such implementationdecisions should not be interpreted as causing a departure from thescope of the present disclosure.

The various illustrative logical blocks, modules, and circuits describedin connection with the aspects disclosed herein may be implementedwithin or performed by an integrated circuit (“IC”), an access terminal,or an access point. The IC may comprise a general purpose processor, adigital signal processor (DSP), an application specific integratedcircuit (ASIC), a field programmable gate array (FPGA) or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, electrical components, optical components,mechanical components, or any combination thereof designed to performthe functions described herein, and may execute codes or instructionsthat reside within the IC, outside of the IC, or both. A general purposeprocessor may be a microprocessor, but in the alternative, the processormay be any conventional processor, controller, microcontroller, or statemachine. A processor may also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor, aplurality of microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration.

It is understood that any specific order or hierarchy of steps in anydisclosed process is an example of a sample approach. Based upon designpreferences, it is understood that the specific order or hierarchy ofsteps in the processes may be rearranged while remaining within thescope of the present disclosure. The accompanying method claims presentelements of the various steps in a sample order, and are not meant to belimited to the specific order or hierarchy presented.

The steps of a method or algorithm described in connection with theaspects disclosed herein may be embodied directly in hardware, in asoftware module executed by a processor, or in a combination of the two.A software module (e.g., including executable instructions and relateddata) and other data may reside in a data memory such as RAM memory,flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a harddisk, a removable disk, a CD-ROM, or any other form of computer-readablestorage medium known in the art. A sample storage medium may be coupledto a machine such as, for example, a computer/processor (which may bereferred to herein, for convenience, as a “processor”) such theprocessor can read information (e.g., code) from and write informationto the storage medium. A sample storage medium may be integral to theprocessor. The processor and the storage medium may reside in an ASIC.The ASIC may reside in user equipment. In the alternative, the processorand the storage medium may reside as discrete components in userequipment. Moreover, in some aspects any suitable computer-programproduct may comprise a computer-readable medium comprising codes (e.g.,executable by at least one computer) relating to one or more of theaspects of the disclosure. In some aspects a computer program productmay comprise packaging materials.

The previous description of the disclosed aspects is provided to enableany person skilled in the art to make or use the present disclosure.Various modifications to these aspects will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other aspects without departing from the scope of thedisclosure. Thus, the present disclosure is not intended to be limitedto the aspects shown herein but is to be accorded the widest scopeconsistent with the principles and novel features disclosed herein.

1. A method of processing portions of packets, comprising: transmittinga first set of at least one pulse; after the transmission of the firstset of at least one pulse, receiving at least one pulse that representsa portion of a packet; and after the reception of the at least onepulse, transmitting a second set of at least one pulse before receivingat least one other pulse.
 2. The method of claim 1, wherein a commonfrequency band is used in the transmission and the reception of thepulses.
 3. The method of claim 1, wherein at least one time hoppingscheme is used to transmit and to receive the pulses.
 4. The method ofclaim 1, wherein the at least one other pulse represents another portionof a packet.
 5. The method of claim 1, wherein the at least one otherpulse represents a remaining portion of the packet.
 6. The method ofclaim 1, wherein the at least one received pulse comprises less than 100pulses.
 7. The method of claim 1, wherein a time duration between thetransmission of the first set of at least one pulse and the transmissionof the second set of at least one pulse is less than or equal to 20microseconds.
 8. The method of claim 1, wherein each of the pulses has atime duration on the order of 20 nanoseconds or less.
 9. The method ofclaim 1, wherein each of the pulses has a frequency band within a rangeof approximately 6 gigahertz to 10 gigahertz.
 10. The method of claim 1,wherein each of the pulses has a fractional bandwidth on the order of20% or more, has a bandwidth on the order of 500 megahertz or more, orhas a fractional bandwidth on the order of 20% or more and has abandwidth on the order of 500 megahertz or more.
 11. The method of claim1, further comprising duty cycling between the transmissions orreceptions of the pulses.
 12. The method of claim 1, further comprisingvarying an inter-pulse time duration between the transmissions orreceptions of the pulses.
 13. The method of claim 12, wherein theinter-pulse time duration is varied based on at least one of the groupconsisting of: a variable pulse repetition period, a variable codingrate, and a time hopping sequence.
 14. The method of claim 1, whereinthe at least one received pulse represents a data symbol that representsat least one data bit.
 15. The method of claim 1, wherein: thetransmitted pulses are associated with portions of other packets; andthe portions of the packets are alternately transmitted and receivedover a common frequency band.
 16. The method of claim 1, wherein:traffic for a multicasting session is carried by the transmitted andreceived pulses; and a common frequency band is used in the transmissionand the reception of the pulses.
 17. The method of claim 1, wherein: thetransmitted pulses are associated with a multicast stream transmitted toa plurality of devices; the at least one received pulse is associatedwith at least one of a plurality of unicast streams received from thedevices; and a common frequency band is used in the transmission and thereception of the pulses.
 18. The method of claim 1, further comprising:identifying a collision between a transmitted pulse and a receivedpulse; and adjusting an error correction scheme based on theidentification of the collision.
 19. The method of claim 18, furthercomprising dynamically determining whether to process the received pulseassociated with the collision.
 20. The method of claim 19, wherein thedetermination is based on a confidence level associated with receptionof received pulses.
 21. An apparatus for processing portions of packets,comprising: a transmitter adapted to transmit a first set of at leastone pulse; and a receiver adapted to receive, after the transmission ofthe first set of at least one pulse, at least one pulse that representsa portion of a packet; wherein the transmitter is further adapted totransmit, after the reception of the at least one pulse, a second set ofat least one pulse before receiving at least one other pulse.
 22. Theapparatus of claim 21, wherein the transmitter and the receiver use acommon frequency band for the transmission and the reception of thepulses.
 23. The apparatus of claim 21, wherein the transmitter and thereceiver use at least one time hopping scheme to transmit and to receivethe pulses.
 24. The apparatus of claim 21, wherein the at least oneother pulse represents another portion of a packet.
 25. The apparatus ofclaim 21, wherein the at least one other pulse represents a remainingportion of the packet.
 26. The apparatus of claim 21, wherein the atleast one received pulse comprises less than 100 pulses.
 27. Theapparatus of claim 21, wherein a time duration between the transmissionof the first set of at least one pulse and the transmission of thesecond set of at least one pulse is less than or equal to 20microseconds.
 28. The apparatus of claim 21, wherein each of the pulseshas a time duration on the order of 20 nanoseconds or less.
 29. Theapparatus of claim 21, wherein each of the pulses has a frequency bandwithin a range of approximately 6 gigahertz to 10 gigahertz.
 30. Theapparatus of claim 21, wherein each of the pulses has a fractionalbandwidth on the order of 20% or more, has a bandwidth on the order of500 megahertz or more, or has a fractional bandwidth on the order of 20%or more and has a bandwidth on the order of 500 megahertz or more. 31.The apparatus of claim 21, further comprising a state controller adaptedto provide duty cycling between the transmissions or receptions of thepulses.
 32. The apparatus of claim 21, further comprising a pulse timingcontroller adapted to vary an inter-pulse time duration between thetransmissions or receptions of the pulses.
 33. The apparatus of claim32, wherein the inter-pulse time duration is varied based on at leastone of the group consisting of: a variable pulse repetition period, avariable coding rate, and a time hopping sequence.
 34. The apparatus ofclaim 21, wherein the at least one received pulse represents a datasymbol that represents at least one data bit.
 35. The apparatus of claim21, wherein: the transmitted pulses are associated with portions ofother packets; and the transmitter and the receiver alternately transmitand receive the portions of the packets over a common frequency band.36. The apparatus of claim 21, wherein: traffic for a multicastingsession is carried by the transmitted and received pulses; and thetransmitter and the receiver use a common frequency band for thetransmission and the reception of the pulses.
 37. The apparatus of claim21, wherein: the transmitted pulses are associated with a multicaststream transmitted to a plurality of devices; the at least one receivedpulse is associated with at least one of a plurality of unicast streamsreceived from the devices; and the transmitter and the receiver use acommon frequency band for the transmission and the reception of thepulses.
 38. The apparatus of claim 21, further comprising an errorcorrection processor adapted to: identifying a collision between atransmitted pulse and a received pulse; and adjusting an errorcorrection scheme based on the identification of the collision.
 39. Theapparatus of claim 38, wherein the error correction processor is furtheradapted to dynamically determine whether to process the received pulseassociated with the collision.
 40. The apparatus of claim 39, whereinthe determination is based on a confidence level associated withreception of received pulses.
 41. An apparatus for processing portionsof packets, comprising: means for transmitting a first set of at leastone pulse; and means for receiving, after the transmission of the firstset of at least one pulse, at least one pulse that represents a portionof a packet; wherein the means for transmitting transmits, after thereception of the at least one pulse, a second set of at least one pulsebefore receiving at least one other pulse.
 42. The apparatus of claim41, wherein the means for transmitting and the means for receiving use acommon frequency band for the transmission and the reception of thepulses.
 43. The apparatus of claim 41, wherein the means fortransmitting and the means for receiving use at least one time hoppingscheme to transmit and to receive the pulses.
 44. The apparatus of claim41, wherein the at least one other pulse represents another portion of apacket.
 45. The apparatus of claim 41, wherein the at least one otherpulse represents a remaining portion of the packet.
 46. The apparatus ofclaim 41, wherein the at least one received pulse comprises less than100 pulses.
 47. The apparatus of claim 41, wherein a time durationbetween the transmission of the first set of at least one pulse and thetransmission of the second set of at least one pulse is less than orequal to 20 microseconds.
 48. The apparatus of claim 41, wherein each ofthe pulses has a time duration on the order of 20 nanoseconds or less.49. The apparatus of claim 41, wherein each of the pulses has afrequency band within a range of approximately 6 gigahertz to 10gigahertz.
 50. The apparatus of claim 41, wherein each of the pulses hasa fractional bandwidth on the order of 20% or more, has a bandwidth onthe order of 500 megahertz or more, or has a fractional bandwidth on theorder of 20% or more and has a bandwidth on the order of 500 megahertzor more.
 51. The apparatus of claim 41, further comprising means forduty cycling between the transmissions or receptions of the pulses. 52.The apparatus of claim 41, further comprising means for varying aninter-pulse time duration between the transmissions or receptions of thepulses.
 53. The apparatus of claim 52, wherein the inter-pulse timeduration is varied based on at least one of the group consisting of: avariable pulse repetition period, a variable coding rate, and a timehopping sequence.
 54. The apparatus of claim 41, wherein the at leastone received pulse represents a data symbol that represents at least onedata bit.
 55. The apparatus of claim 41, wherein: the transmitted pulsesare associated with portions of other packets; and the means fortransmitting and the means for receiving alternately transmit andreceive the portions of the packets over a common frequency band. 56.The apparatus of claim 41, wherein: traffic for a multicasting sessionis carried by the transmitted and received pulses; and the means fortransmitting and the means for receiving use a common frequency band forthe transmission and the reception of the pulses.
 57. The apparatus ofclaim 41, wherein: the transmitted pulses are associated with amulticast stream transmitted to a plurality of devices; the at least onereceived pulse is associated with at least one of a plurality of unicaststreams received from the devices; and the means for transmitting andthe means for receiving use a common frequency band for the transmissionand the reception of the pulses.
 58. The apparatus of claim 41, furthercomprising means for error correcting by: identifying a collisionbetween a transmitted pulse and a received pulse; and adjusting an errorcorrection scheme based on the identification of the collision.
 59. Theapparatus of claim 58, wherein the means for error correctingdynamically determines whether to process the received pulse associatedwith the collision.
 60. The apparatus of claim 59, wherein thedetermination is based on a confidence level associated with receptionof received pulses.
 61. A computer-program product for processingportions of packets, comprising: computer-readable medium comprisingcodes executable by at least one computer to: transmit a first set of atleast one pulse; receive, after the transmission of the first set of atleast one pulse, at least one pulse that represents a portion of apacket; and transmit, after the reception of the at least one pulse, asecond set of at least one pulse before receiving at least one otherpulse.
 62. A headset for wireless communication, comprising: atransmitter adapted to transmit a first set of at least one pulse; areceiver adapted to receive, after the transmission of the first set ofat least one pulse, at least one pulse that represents a portion of apacket; wherein the transmitter is further adapted to transmit, afterthe reception of the at least one pulse, a second set of at least onepulse before receiving at least one other pulse; and a transduceradapted to provide an audible output based in part on the received atleast one pulse.
 63. A watch for wireless communication, comprising: atransmitter adapted to transmit a first set of at least one pulse; areceiver adapted to receive, after the transmission of the first set ofat least one pulse, at least one pulse that represents a portion of apacket; wherein the transmitter is further adapted to transmit, afterthe reception of the at least one pulse, a second set of at least onepulse before receiving at least one other pulse; and a display adaptedto provide a visual output based in part on the received at least onepulse.
 64. A medical device for wireless communication, comprising: atransmitter adapted to transmit a first set of at least one pulse; areceiver adapted to receive, after the transmission of the first set ofat least one pulse, at least one pulse that represents a portion of apacket; wherein the transmitter is further adapted to transmit, afterthe reception of the at least one pulse, a second set of at least onepulse before receiving at least one other pulse; and a sensor adapted togenerate sensed data to provide pulses to be transmitted by thetransmitter.